Abstract
The amino acid sequence of apovitellenin I from hen egg yolk was determined using both automatic and manual procedures; it comprises 82 residues. Hen apovitellenin, shows considerable homology with emu apovitellenin I, which contains 84 residues. Besides 2 deletions in the sequence, the hen protein differs in 28 positions from the emu protein; 26 of these positions may have arisen from single base changes. The changes are largely conservative ones, which suggest that the structure and function have been preserved despite extensive mutation.